Shoes having height adjustable heels are known in which the change in height is obtained by adding a separate element within the interior of the shoe or at the end of the heel or by a height-adjustable telescopic arrangement. The wearer must constantly be in possession of the separate height-adjusting element and must make sure it has not been left behind when going out. Furthermore, the insertion and the removal of this element or the adjustment of the telescopic system are relatively time consuming and are relatively delicate operations which require the wearer to remove the shoes and remain in an uncomfortable position during the adjustment period. Moreover, in the particular case of adjustment by means of a telescopic system, the heel and sole assembly is tilted as the unit upwards or downwards in relation to its initial position, as the heel is respectively lowered or raised. Therefore, the sole is no longer applied flat against the ground, but is inclined upwards or downwards. A feeling of discomfort for the wearer and a rapid tiring of the feet is the result from this inclination.
According to U.S. Pat. No. 3,464,126, moreover a shoe having a height-adjustable heel is known which does not present the abovementioned disadvantages. This shoe comprises a fixed support element forming the heel and sole, a pivoting element positioned above the rear part of the fixed element and articulated upon the latter in such a way that it can be raised or lowered in relation to the fixed element by means of manually activating the locking mechanism which is intended to lock the pivoting piece in the position corresponding to the height chosen for the heel, and a prestressed spring means is arranged between the fixed support element and the pivoting element and is intended to pull the latter towards its elevated position.
The locking mechanism is made up of two linch pins transversally mounted in an opening formed in the fixed support element of the shoe, said linch pins being pulled by a spring towards the outside so as to penetrate into pairs of receptor openings vertically positioned on two lateral sides protruding under the pivoting element and overlapping the fixed support element.
To release said linch pins from the receptor openings into which they protrude, there is provided on the overlapping sides of the pivoting element, two knobs provided with studs penetrating into said pairs of receptor openings and capable of withdrawing said linch pins from the receptor openings when the knobs are simultaneously pressed in. The pivoting element is then released and can be placed in another position for which the pins penetrate into another pair of receptor openings.
Although operating in a satisfactory manner, such a locking mechanism cannot in practice be used by reason of it unaesthetic appearance. The knobs and overlapping sides are visible on both sides of the shoe so that they cannot be used for the manufacture of shoes that bear fine brands. Furthermore, the heel of the pivoting element overhangs the fixed support element.